It is a goal pursued in the long-time by many scientists and engineers in the engineering field to accurately and intuitively display and present stress field evolution of complex heterogeneous materials such as rock and concrete, as well as engineering structures, which is also a basis and key to solving many engineering practical problems.
The existing stress field measurement methods mainly include two types, experimental measurement and numerical simulation. The experimental measurement mainly involves methods such as on-site monitoring and laboratory measurement, which mainly rely on sensors to measure local points, have difficulty in forming full-field stress distribution, and have a large cost on measurement. Although the numerical simulation can better show stress field distribution, its computational accuracy is subject to material parameters, model meshing, and boundary condition settings.
There is also a relatively mature full-field stress measurement method in the conventional technology, that is, photoelasticity, which generally quantifies the distribution of the stress field by determining the number of fringe orders. However, such experimental method is limited to the processing of models with simple geometric shapes. For models with non-continuous structures embedded with pores, cracks and particles, the distribution characteristics of the photoelastic fringes are abnormally complex and thus traditional quantification method hardly applies; and even the digital photoelastic method developed in recent years cannot realize the extraction and quantification of the full-field stress when the complex structure is subjected to high external loads continuously applied under fixed light field conditions.